Suboptimal Sleep Associated with Elevated Risk of Developing a Chronic Disease

Five hours or less hours of sleep per night at 50 years of age was associated with a 25% higher risk of mortality over 25 years of follow-up.

People who get 5 hours or less of sleep per night who are 50 years of age are 20% more likely to be diagnosed with a chronic disease and 40% more likely to be diagnosed with 2 or more chronic diseases over 25 years in comparison to those who sleep for up to 7 hours, according to a study published in PLOS Medicine.

“Multimorbidity is on the rise in high income countries, and more than half of older adults now have at least two chronic diseases. This is proving to be a major challenge for public health, as multimorbidity is associated with high health care service use, hospitalizations, and disability,” said lead study author Severine Sabia, MD, UCL Institute of Epidemiology & Health, in a press release. “As people get older, their sleep habits and sleep structure change. However, it is recommended to sleep for 7 to 8 hours a night—as sleep durations above or below this have previously been associated with individual chronic diseases.”

The investigators evaluated the impact of sleep duration on the health of more than 7000 men and women at 50, 60, and 70 years of age from the Whitehall 2 cohort study. They focused on the relationship between how long each participant slept for, mortality, and whether they had been diagnosed with 2 or more chronic diseases over 25 years.

The study authors found that of 5 hours or less hours of sleep per night at 50 years of age was associated with a 25% higher risk of mortality over the 25 years of follow-up. The investigators noted that short sleep duration elevates the risk of chronic disease, which subsequently increases the risk of death.

Sabia added that the findings show that short sleep duration is also associated with multimorbidity.

“To ensure a better night’s sleep, it is important to promote good sleep hygiene, such as making sure the bedroom is quiet, dark and a comfortable temperature before sleeping,” Sabia said in the release. “It’s also advised to remove electronic devices and avoid large meals before bedtime. Physical activity and exposure to light during the day might also promote good sleep.”

The researchers also assessed whether sleeping for 9 hours or more per night affected health outcomes. They found no clear association between long sleep durations at 50 years of age and multimorbidity in healthy people.

If a participant was previously diagnosed with a chronic condition, long sleep duration was associated with an approximately 35% higher risk of developing another illness. The researchers said that this could be due to underlying health conditions impacting sleep.

Study limitations included the researchers use of self-reported data on sleep, which can be subject to reporting bias, and the data being used from 4000 participants whose sleep was measured via electronic device.

Additionally, data on sleep quality were only available for individuals between 60 and 70 years of age.

Finally, the Whitehall 2 study only included members of the civil service who were all employed when recruited to the study and likely to be healthier than the general population.

REFERENCE

Five hours’ sleep a night linked to higher risk of multiple diseases. UCL. October 19, 2022. Accessed November 16, 2022.

https://www.ucl.ac.uk/news/2022/oct/five-hours-sleep-night-linked-higher-risk-multiple-diseases#:~:text=Five%20hours'%20sleep%20a%20night%20linked%20to%20higher%20risk%20of%20multiple%20diseases,-19%20October%202022&text=Getting%20less%20than%20five%20hours,study%20led%20by%20UCL%20researchers